In the "Create Objects" interface, check the "barycenter" option under Reference Object.

If you don't do this, then when Gravity Simulator converts your orbital elements to state vectors, it uses the mass and position of the Reference object only. With barycenter checked, it adds the mass of the star + the white dwarf, computes their center of mass and uses that for the position.

Like I said in another thread, Gravity Simulator does not yet provide output for barycentric systems. So your results will be orbital elements with respect to a single object, rather than with respect to a barycentric system. (i.e. they'll be meaningless unless you're really good with Excel and the conversion between orbital elements and state vectors, as the math can be done externally to the simulation).

It's not that hard for me to incorporate such output as it would use existing blocks of code. Just haven't gotten around to it yet.

In the "Create Objects" interface, check the "barycenter" option under Reference Object.

If you don't do this, then when Gravity Simulator converts your orbital elements to state vectors, it uses the mass and position of the Reference object only. With barycenter checked, it adds the mass of the star + the white dwarf, computes their center of mass and uses that for the position.

Like I said in another thread, Gravity Simulator does not yet provide output for barycentric systems. So your results will be orbital elements with respect to a single object, rather than with respect to a barycentric system. (i.e. they'll be meaningless unless you're really good with Excel and the conversion between orbital elements and state vectors, as the math can be done externally to the simulation).

It's not that hard for me to incorporate such output as it would use existing blocks of code. Just haven't gotten around to it yet.

Thought something weird was going on...

So I guess there's not much point in me trying this sort of thing until the output is sorted out for barycentres? I don't fancy doing all the conversions manually!

Imagine a barycenter as a ficticious object. It's mass is the combined mass of 2 objects. It's location is the center of mass of those 2 objects. The center of mass is just the weighted average of the positions.

In reality a barycenter is not an object. It is just an empty point in space. But any object that orbits the pair of objects from a great enough distance will behave as if it is orbiting the ficticious object.

Press Create This creates a planet in orbit around star A. Gravity Simulator uses the combined masses of Star A and Planet Aa when converting the orbital elements you provided into the state vectors that Gravity Simulator uses to crunch the numbers.

Press Create This creates a planet in orbit around star B. Gravity Simulator uses the combined masses of Star B and Planet Ba when converting the orbital elements you provided into the state vectors that Gravity Simulator uses to crunch the numbers.

Press Create This creates a planet in orbit around the barycenter of star A and star B. Gravity Simulator creates a ficticious object whose mass is the combined mass of Star A and Star B, and whose position is the weighted average of the position of Star A and Star B. It then uses the combined masses of the ficticous object and Planet ABa when converting the orbital elements you provided into the state vectors that Gravity Simulator uses to crunch the numbers. The ficticious object is not used in the number crunching, only in creating the object, for the purpose of computing the state vectors of the planet.

You should now have the 5-object system described above.

When viewing the system, select Star A as the focus object. Then use the F/A button on the Graphics Options interface to toggle back and forth between Floating Mode and absolute Mode. Pressing F places you in the floating mode, and the screen is centered on the system barycenter. Pressing A returns you to absolute mode and the screen is centered on Star A.

In the case of your system, all the planets orbit the pair, so you would select barycenter when creating all objects except the white dwarf.

Thanks for posting all that, but that's almost exactly what I did. The only differences are that Lusor was 1.51 solar radii, I actually entered "0" into the Eccentricity and Inclination boxes for all the objects, and I put a leading "0" before all the values that were less than 1 (i.e. 0.626 instead of .626). Otherwise it was the same.

I'll try to make it again following your instructions exactly and see if it still screws up.

Though as a suggestion, one thing you might consider is to actually make the barycentre an object in the program - that way we can explicitly tell it to use it as the reference object instead of the star.